Discrete Automatic -- A Handgun Design

[ke6guj]

Why would the integrated grip safety also release the slide? That means when you eject your mag, your slide will either slam forward when the mag leaves, or when you insert the new mag your slide will release.

because that is the way that the HK works. you run the gun to slide lock, relax your grip since you aren't ready to fire, drop old mag, insert new mag, squeeze grip and the slide drops.

[Icypu]

because that is the way that the HK works. you run the gun to slide lock, relax your grip since you aren't ready to fire, drop old mag, insert new mag, squeeze grip and the slide drops.

Is it possible to hold the gun with only your thumb, web of hand and side of fingers. I'd probably drop it.

What happens if you hold the grip safety down while you change your mag?

[ke6guj]

Is it possible to hold the gun with only your thumb, web of hand and side of fingers. I'd probably drop it.

you aren't barely holding the gun, you just aren't squeezing it with enough pressure to activate the front grip. now this is on the P7, don't know what the OP's design strength would be/

What happens if you hold the grip safety down while you change your mag?

don't know, never tried to hold the grip in while swapping out a mag. not really designed for that.

[dwightlooi]

Is it possible to hold the gun with only your thumb, web of hand and side of fingers. I'd probably drop it.

What happens if you hold the grip safety down while you change your mag?

It won't matter. The slide drops after you release and re-engage the grip safety. keeping it compressed does not drop the slide. Releasing it does not drop the slide. squeezing it from a released state drops the slide. So relax the grip and drop the mag or drop the mag and release the grip. It doesn't matter. It is when you squeeze the lever back again that the slide drops. It is perfectly natural and the fastest way to operate a slide release -- no need to use your thumb or rack the slide back. Insert, squeeze, slam you are ready to fire.

You relax the grip, you don't let go completely. You don't have to completely unfurl your fingers -- you just relax them enough to let the lever pop back out 8~10mm. Let me put it this way... have you ever held a pair of spring loaded thongs for BBQ or whatever? Closing your grip allows you to pick up that burger. Relaxing it doesn't actually drop the thongs does it? It just opens the thongs so you release the burger patty. The whole point about putting the lever in front instead of the rear is that it's operation is both natural and deliberate. You can draw and point the gun with or without applying about 6~8 pounds of pressure and 10mm of travel to that lever. You can relax your grip and still securely hold the gun and point it at the target. You cannot do that with a tang safety like a 1911 or an xD.

IMHO, the HK P7 has the most natural operating ergonomics and the front strap is clearly superior to a slide safety or a tang safety or a trigger safety. it is better than a slide safety because there is no way you can forget to disengage it -- the natural instinct is to tighten your grip, it is releasing it and safing the gun that is deliberate. It is better than a tang safety because you can deliberately relax your fingers and safe the gun while still securely holding it; you cannot deliberately move the web of your hand back. And, finally, because the gun's safeties are kept separate from the gun's trigger you do not need to encumber the trigger with a long 6~10mm pull like a Glock, xD, M&P or PPQ. The trigger can be as light and as short in pull as a custom 1911 without it being unsafe and without having any thumb safety to fool around with.

[dwightlooi]

Do you mind if I copy and paste your OP over at the HK PRO forum? Or have you already? I'd like to read their opinions.

http://www.hkpro.com/forum/hk-handgun-talk/

Go ahead... knock yourself out.

[tophatjones]

It is based on the P7 ergonomics... however it corrects a few flaws of the P7.

(1) It is not gas retarded. This means that it can handle the 40 or the 45 or the 357 sig without having a ridiculously heavy slide (P7M10) or an oil buffer (P7M7) because the opposed piston delay is simply inadequate above 9mm recoil levels.

(2) Because it is not gas retarded, it wouldn't heat up the area above the trigger finger to fry pan temperatures after a half dozen mags.

(3) It is not a squeeze cocker but a single action pistol with a front strap acting as a safety. With the firing pin blocked, the sear blocked and the trigger disconnected it is just as safe despite being fully cocked all the time. You lose re-strike capability, but you should rack and eject instead of re-striking a dead primer anyway. And, because it is single action only you can have a short and light single action pull. Finally, because it is not a squeeze cocker, the front strap mechanism is a lot simpler and a lot lighter.

I really like #3, but have a slight bone to pick with #1 and #2. The gas retarded system is an engineering decision; it comes with advantages and disadvantages like any other. The gas retarded system has the following advantages over the tilting barrel design: 1) less barrel+slide mass required and 2) lower profile, due to the barrel not needing to tilt down. What is the combined mass of your barrel and slide? .40 caliber striker fired, tilting barrel designs need a relatively large barrel+slide mass to mediate slide velocity because of the larger momentum of the .40 caliber round.

[dwightlooi]

How about if you integrate a laser, and that big safety can activate it? Better yet, a switch can configure the behavior of the switch: Laser On, Off, or Pulse on Fire(target practice)?
There's usually room in the grip, behind the
magazine well, which can hold the batteries.

Actually, I thought about that. I don't believe that most shooters want a laser so I don't think it should be integral to the gun. However, since we have a lever provisions can be made for a ferrite field effect switch (no actual contact and completely waterproof) to be activated inside the grip when the lever is squeezed. This does nothing but closes the contact circuit between a pair of gold plated contacts under the frame in front of the trigger guard. How you use that (or not at all) is up to you. It can be used to trigger a laser or flashlight or nothing at all.

[king kong]

if this was something I could actually purchase in California I'd be interested. nice job

[96snake]

Didn't hk already make this?

[dwightlooi]

I really like #3, but have a slight bone to pick with #1 and #2. The gas retarded system is an engineering decision; it comes with advantages and disadvantages like any other. The gas retarded system has the following advantages over the tilting barrel design: 1) less barrel+slide mass required and 2) lower profile, due to the barrel not needing to tilt down. What is the combined mass of your barrel and slide? .40 caliber striker fired, tilting barrel designs need a relatively large barrel+slide mass to mediate slide velocity because of the larger momentum of the .40 caliber round.

Well, that is not exactly true... the P7 has a low profile slide (height wise) but it does not have a light slide. It actually has a pretty darn heavy spring. Basically, the P7 is NOT a locked breech gun. Think of it as a straight blow back gun like a Walther PP/PPK with a gas cylinder under the barrel which provides a little extra resistance to the reward movement of the slide until the pressures fall off. This resistance does not exceed the force pushing back on the slide... in fact it is considerably less than that. The reason is simple. The gases push against the slide on one end of the force system over an area the size of the bore, it pushes against the piston which is much smaller than the bore. The pressures being about the same it the greater surface area of the bore wins. The piston adds maybe a 25% extra resistance and only momentarily. But this, along with a sufficiently heavy slide and a stiff recoil spring, is enough to allow a straight blow back design to be uprated from 380 ACP to 9mm luger. It is NOT enough however to tame the 40 S&W hence the P7M10 has a slide which is almost 70% heavier and much taller. All that extra height is to add steel for added weight!

In a tilting barrel gun you have five advantageous. Firstly, the initial recoil (when the bullet is still in the barrel) is applied to not just the slide but the combined mass of the slide AND the barrel. So the slide can in fact be lighter. Secondly, you are using the slide and barrel mass moving back a short distance to keep the breech locked. You are not really relying on the spring to do so. The spring is there to slow the slide AFTER unlocking and to close the action after cycling. Hence, tilting barrel systems always have lighter springs than blow back or gas delayed systems. Thirdly while a gas retard, having a stationary barrel a spring around the barrel not a guide rod under it, allow for reduced vertical height it actually increases the width of the pistol. While a tiling barrel system may have an additional 5mm of height it can actually be slimmer on the sides. Fourth, because the unlocking event is timed by the cam and the lugs under the barrel which drops it after the prescribed travel this can be adjusted for each caliber offered simply by modifying the barrel. Sure beats adding weight to the slide or changing the design of the pistol. Finally, that gas cylinder gets hot -- bloody darn hot after you fire 4 or 5 mags. That is why the P7s gained the plastic heat shield over the trigger area (which it's PSP predecessor didn;t have). Even with this, I CANNOT touch that area with my trigger finger after 5 or 6 mags shot in 5 mins without saying "ouch"! This is NOT a critical flaw given that P7s are unlikely to see a lot of combat scenarios where 5 or 6 mags are fired in rapid succession. And, this can be easily overcome by wearing gloves. But this is certainly NOT an advantage to the design.

One of the theoretical advantage of the gas retarded system (or blow back systems for that matter) is the stationery barrel being more accurate. However in practice I find well tolerances tilting barrel systems just as accurate if not more so than stationery barrel guns. The Baer 1911 or the Walther PPS will out shoot and equal the P7 in accuracy respectively. I know... I own and bench fired them all. To have a very accurate tiling barrel gun the tightness and consistency of the lockup when the gun is in battery is paramount. A Baer 1911 guarantees 1.5" groups at 50 yards because it is intentionally machined to not fit together. A guy then files the rails and lugs down by hand -- a little at a time until the gun barely fits and goes into battery. The super tight lockup returns super tight groups. This is not practical for mass production. So, I made it simpler. The horizontal accuracy is guaranteed by the V-notch mating of the slide to the barrel in the rear of the ejection port. Unlike square cuts, V-notches self-indexes to zero clearance. The vertical accuracy is assured by the barrel being over toleranced to not go into battery. Material is manually removed on from it until it barely does -- hence the hand fitted part. The rails really aren;t that important so those are just CnCed with tight but non-interfering tolerances. If the barrel is perfectly aligned hoziontally and vertically to the slide and the sights are on the slide the pistol will be very accurate.

[dwightlooi]

Didn't hk already make this?

No, it draws from the best aspects of Helmut Weldle's HK P7. But it is fundamentally a completely different pistol in operating principle. The P7 is a gas delayed gun, this is a tilting barrel gun. The P7 is a squeeze cocking design, this is a single action only design with a front safety lever.

[dwightlooi]

if this was something I could actually purchase in California I'd be interested. nice job

No chance. Even if this got made, there is no way it'll make it onto california's handgun roster. No handguns will ever make it on there any more, so what you have on there is what you got. And that list will shrink as old models become discontinued and/or manufactures fail to pay the $2500/year/model to keep each of them on there.

Chamber indicator or not. Magazine Disconnect or not. You'll need a microstamping firing pin and chamber to make the list now. It is not a viable technology and there is no existing machinery to implement it. That is why there has been ZERO new handguns since they started enforcing microstamping. Eventually, over the next decade or more, the list will drop to zero and you'll not be able to buy a new handgun in California effecting a defacto handgun ban.

That is the goal and unless the law changes or is struck down in the courts, that is what's going to happen. The anti's of course are laughing all the way to bed!

[orangeusa]

A Beretta Nano with HK P7 loader. And I think you meant discreet.
Magazine disconnect - are you serious?

.

[jimsguns]

Looks cool, just omit the "read user manual" crap off the frame.

[dwightlooi]

A Beretta Nano with HK P7 loader. And I think you meant discreet.
Magazine disconnect - are you serious?

.

Not even close. The Nano is a smaller pistol and it is a half-cocked, long pull, trigger safety pistol. This is a notably larger pistol with a grip long enough to make contact with all fingers. It is a true single action gun -- the striker is NOT half-cocked it is fully cocked like a 1911's hammer is fully cocked. It has the P7 front strap lever which when depressed makes the gun ready to fire and when relaxed safes the gun completely. Unliek the P7, the lever does not cock or decock the striker, it simply engages or disengages the safeties. The front lever naturally serves as the slide release when it is depressed from a relaxed state.

I have no problems with a magazine disconnect feature as long as it is something the user can enable or disable. Basically, there is a pin which you can insert which will always hold the disconnect in the same position as if there is a magazine inserted. The manual tells you how to do it. And, you can set one way or the other in a few minutes. So, it's really up to you if you want it.